Roller bit



Feb. 10,1931. J. c. STOKES 1,791,767

' ROLLER snori inal Filed ug. 23. 192':

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A 6 I W 43 5 INVENTOR. John Stokes ATTORNEYS.

Patented Feb. 10, 1931 UNITED STATES IPATEIN oFFi'ce JOHN c. s'roxns, or nousron, TEXAS, sssreuoa'ro REE-D ROLLER BIT comm, or

nous'ron, TEXAS, A CORPORATION or raxas ROLLER BIT Original application filed August 23, 1927, Serial No. 214,826. Divided and this application-filed.

January 26, 1928.

This invention relates to deep well drilling apparatus, and more particularly to roller bits of the type disclosed in my application for Letters Patent of the United States, filed August 23rd, 1927, Serial No. 214,826, of which this application is a division.

The invention has for its object the 'provision of a roller bit embodying means, independent of its roller cutters, to effect cleaning of its roller cutters without practical interference with the free revolution thereof.

Other objects will hereinafter appear.

The preferred embodiments of the Invention are illustrated in the accompanying drawings, in which Fig. 1 is a fragmentary sectional side elevation of a roller bit with the roller cutters and cleaning devices mounted therein; Fig. 2 is a detail end elevation of the mounting taken on the line 2-2 of Fig. 1; Fig. 3 is a detail end elevation of the mounting illustrated in Fig. 4, which is a side elevation partly in section.

Referring specifically to the Figs. 1 and 2 of the drawings, the bit head is indicated at 1, and has depending side bearing pro ections 1-a to support the cross roller cutter pin 2. Upon pin 2 is a sleeve 3 having in- 'tegral eccentric portions 3-a and 3- 6 to support respectively disc-like plates 4 and roller cutters Sectional bushings 6 are 111- ter osed between plates 4 and portions 3-a, an sectional bushings 7 are interposed between cutters 5 and portions 3-1). It will be observed that the inside diameter of the cutters 5 and the plates 4 is suilicient to per- -mit them to he slipped over the eccentric portions 3a and 3-6; and the bushings 6 and 7 are made sectional in order that they may be placed about the eccentric portions 3-a, and 3-b, respectively.

The plates 4 are freely revoluble, and revolution thereof may be effected by the cutters 5. The eccentric revolution of the cutters and plates is attended by movement of the lateral surface of each cutter with respect to the lateral surfaces of adjacent plates. The material adhering to the cutters is scraped off by such movement, and as the plates and cutters revolve in the same direc- Serial No. 249,528.

tion no practical resistance is offered to the free revolution of the latter.

It will also be noted that the lowermostassembled cutters and plates in'therecess provided therefor in the bit head, and insert pin 2 in the head and through sleeve 3. Exposure to dirt or other foreign matter of the bearing surfaces of the parts is, therefore, unnecessary.

This invention provides means whereby groups of cutters and cleaning devices may be quickly and easily inserted and removed as units.

Figs. 3 and 4 are illustrative of an assembly embodying a pin 8, cutters 9, and disc-like plates 10, said cutters being mounted upon said pin, and said plates being mounted upon eccentric bushings 11, bushings 11 being held in place on pin 8 by suitable keys 12. j

The relative disposition and revolution of the cutters 9 and 10 of Figs. 3 and 4 are the same as the relative disposition and revolution of the cutters 5 and plates 4, shown in Figs. 1 and 2. a

The invention is not limited to the specific embodiments above described, and various changes may be made without departure from the scope of the following claims.

I claim:

1. In a roller bit, a head having a cutter recess, a plurality of disc shaped roller cutters, a plurality of disc shaped cleaning devices, and a support mounted in said recess and having aplurality of eccentric portions, and sectional bushings for said portions, said cutters and cleaning devices being so mountroller cutters, a plurality of disk shapedv cleaning devices, and a one piece support havmg a plurality of eccentric portions, and sectional bushings for said portions, said cutters and cleaning devices being so mountable on said bushin that said cleaning devices are adjacent an eccentrically rotatable with re- 5 spect to said cutters, and said cleaning devices are rotatable on one common axis and said cutters are rotatable on another common axis. 3. In a roller bit, a head having a cutter recess, a plurality of disk shaped roller cutters, a plurality of disk shaped cleaning devices, and a su port mounted in said recess and having a p urality of eccentric portions, and sectional bushings for said portions, said cutters and cleaning devices bein so mountable on said bushings that said 0 caning devices and said cutters are adjacent eachother, said cleaning devices are rotatable on one common axis, and said cutters are rotatable on another common axis below the axis of rotation of said cleanin devices.

In testimony whereo I hereunto afiix my signature.

JOHN C. STOKES. 

